StepFun

StepFun (阶跃星辰) is a Shanghai-based large-model startup developing foundational AI models and pushing an "AI + terminal" strategy. In early 2026 it closed a RMB 5 billion+ Series B+ round — the largest single financing in China's large-model track over the preceding 12 months — with investors including Shanghai SDIC Pioneer Fund, Guoshou Equity, Tencent, Qiming Venture Partners, and 5Y Capital doubling down, among others . Founded in 2024 per a 5Y Capital report, the company is led by founder and CEO Jiang Daxin (姜大昕) . StepFun has been actively building partnerships to extend its models into physical-world applications: it signed a strategic cooperation with Yuanli Lingji (原力灵机) in April 2025 to develop "RoboAgent" for embodied intelligence scenarios , open-sourced the music-generation model ACE-Step with ACE Studio in May 2025 , and formed a joint venture framework with Huayi Brothers Media (欢喜传媒) in November 2025 for film, interactive entertainment, and gaming . The company directs its funding toward foundational model R&D and accelerating its terminal-device strategy .